78330015625 has 21 divisors (see below), whose sum is σ = 97955015691. Its totient is φ = 62636025000.

The previous prime is 78330015623. The next prime is 78330015683. The reversal of 78330015625 is 52651003387.

The square root of 78330015625 is 279875.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 3 ways, for example, as 68624613369 + 9705402256 = 261963^2 + 98516^2 .

It is not a de Polignac number, because 78330015625 - 2¹ = 78330015623 is a prime.

It is a super-2 number, since 2×78330015625² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78330015623) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 20 ways as a sum of consecutive naturals, for example, 34983256 + ... + 34985494.

Almost surely, 2^78330015625 is an apocalyptic number.

78330015625 is the 279875-th square number.

78330015625 is the 139938-th centered octagonal number.

It is an amenable number.

78330015625 is a deficient number, since it is larger than the sum of its proper divisors (19625000066).

78330015625 is an frugal number, since it uses more digits than its factorization.

78330015625 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4508 (or 2244 counting only the distinct ones).

The product of its (nonzero) digits is 151200, while the sum is 40.

The spelling of 78330015625 in words is "seventy-eight billion, three hundred thirty million, fifteen thousand, six hundred twenty-five".